Gel purification of RNA.

For many applications, including size selection of RNAs and purification of in vitro transcription products, it is necessary to purify RNAs on a denaturing gel. This procedure describes how to purify transcripts that have been synthesized in vitro. It is useful for labeled or unlabeled RNAs when sufficient mass is present. It can also be used to isolate small RNAs. In general, RNA purification by denaturing gel electrophoresis is practical only when the size of the desired RNA is 600 nucleotides or less.